Socket



R. G. PHELPS SOCKET May 16, 1939.

Filed Feb. 12, 1957 Fig. 2.

Inventor Roscoe G. Phelps,

Attorney.

Patented May '16, 1939 Roscoe G. Phelps, Cleveland, Ohio, assignor to General Electric Company, a corporation of New York Application February 12, 1937, Serial No. 125,409

. 17 Claims.

The present invention relates to electric sockets of the type having provisions for preventing short-circuit oi the terminals thereof when the socket is empty. Sockets of this type 5 are particularly adapted for use in locations where there is some chance that pieces of tin foil or other metallic particles may fall into empty sockets and short-circuit the exposed terminals.

For example, the socket is well adapted ior use with strings of decorative lights, such as Christmas. tree lights.

The object of my invention is to provide an improved construction and arrangement in sockets of this type and for a consideration of what I 15 believe to be novel and my invention attention is directed to the accompanying descriptionand the claims appended hereto. p

In the accompanying drawing, Fig. 1 is a sectional elevation of a socket embodyin y inven-- tion; Fig. 2 is a view similar to Fig. 1 with a lamp in the socket; Fig. 3 is an exploded perspective view of the diaphragnr closing the lower end of the screw shell and the contact associated therewith, and Fig. 4 is a sectional elevation of a 25 modification.

Referring to the drawing, the socket has a base or husk I of suitable molded insulating material. The base has a cylindrical recess 2 at its upper end in which the parts of the socket are asserti- 30 bled. At the lower end of the recess is a-disk 3 of insulating material which rests on a shoulder 4. At the center of the disk is a rivet 5 which secures a terminal 6 to theunderside of the disk. The head 1 of the rivet is on the upper side of the disk and serves as a. contact for connecting the terminal 5 with thecenter terminal of the socket in a manner which is described below. Near the periphery of the disk is a rivet 8 which secures a terminal 9 to the underside of the disk. The head 40 In of the rivet is on the upper side of the disk and serves as a contact for connecting the terminal 8 to the screw shell in a manner which is described below. In .the use of the socket the. terminals 6 and 9 are respectively connected to one of the line conductors. The line conductors extend from the terminals through an opening I I in the lower end of the base. The space surrounding the terminals and conductors may be filled with a suitable insulating cement for holding the conductors in place. The manner of connecting the conductors to the terminals is not shown, it being well understood in the art. On the upper side of the disk 3 is a spacing sleeve I2 of insulating material. 0n the upper 55 edge of the sleeve I? rests an assembly which minal of the socket and the lower end of which is 1 0 directly above and spaced irom the contact 1. When the socket is empty the contact I1 is therefore insulated from the line conductors. On the upper side of the diaphragm i4 is a screw shell I9 which is secured in the recess 2 by frictional engagement of a flange with the side walls 2| of the base. At the lower end of the screw shell is an inwardly projecting flange 22 having a depression therein (not shown) into which the tongue l5 fits. The tongue [5 makes contact with a portion'23 of the flange 22. The metal stamping I3 is cut away to provide a flexible tongue 24 having a downwardly extending portion 25 at its free end which is directly above and is normally spaced from the contact ill. The intermediate portion of the tongue 24 is annular in shape, the lower end of the contact I! extending through and being spaced from the edges of the opening 26 therein. l When a plug is threaded into the socket, as shown in Fig. 2, the centercontact I8 of the plug engages the center terminal ll of the socket and forces it downward into engagement with the contact 1, thereby completing a circuit from the line terminal 6 to the center terminal 11. The downward movement of the terminal ll is made possible by flexing of the diaphragm. At the same time the tongue 24 which rests against the lower side of the diaphragm is forced downward until the downwardly extending portion 25 is forced into engagement with the contact Hi thereby completing a circuit from the line terminal 9 to the screw shell. When the plug is unthreaded from the shell, the diaphragm and the tongue 24 return to the position shown in Fig. .1 thereby breaking 4 the circuit from the line terminals 6 and 8 to the screw shell I!) and the center terminal ll of the socket. When the socket is empty the exposed terminals of the socket are therefore insulated and there is no danger of shortcircuiting the terminals by pieces of tin foil or other metallic particles which may fall into the empty socket.

In order to facilitate assembly of the socket, the disk 3, the spacing sleeve l2, the assembly comprising the metal stamping l3-and the dia- 55 Fig. 4 shows a modification oi the socket in which the function of the sleeve 2! is filled by a sleeve 28 which is integral with the lower end of the screw shell. The other parts of the socket are of the same construction as the socket shown in Figs. 1 to 3, inclusive, the corresponding parts being denoted by the same reference characters. In the assembly of this socket. the diaphragm I4 with the stamping l3 fixed thereto is inserted through the lower end of the sleeve 28. The tongue I5 makes contact with a flange 29 at the upper end of the sleeve 28. The spacing sleeve and the disk 3 are then inserted, the position of the disk 3 being such that the contact Ill is'in alignment with the contact 25. The partsare then held in assembled relation by spinning over a flange-30 at the lower end of the sleeve 23. The screw shell with its assembled parts may-then be pressed into the base and held therein by frictional engagement between the side walls II of the base and the flange at the upper end of the screw shell.

The operation of the socket shown in Fig. 4 is identical with the operation of the socket shown in Figs. 1 to 3 inclusive.

What I claim as new and desire to secure by Letters Patent 01 the United States, is:

1. In. an electric socket, a screw shell, a resilient diaphragm closing the lower end of the screw shell, said diaphragm being fixed at its edges, a center contact carried by said diaphragm and adapted to be engaged by the center contact of a plug threaded in the shell whereby part of the diaphragm is moved downward, a contact connected to said shell and arranged to be moved downward by said movement of the diaphragm,

and contacts adapted to be connected to ,line conductors and arranged to be engaged by said center and shell contacts when in their downward positions, said center and shell contacts being separated irom said line contacts when in their normal positions.

2. In an electric socket, a screw shell, a disk of insulating material closing the lower end of the shell, said disk being flxed atits edges and having an intermediate resilient part arranged to be flexed downward by a plug threaded in the shell, 9. contact adapted to-be connected to a line conductor, and means for completing a circuit from said contact to said shell upon downward movement of said part, said' circuit being normally open wherebysaid shell is insulated when empty.

3. In an electric socket, a screw shell, a disk of insulating material closing the lower end of the shell, said disk being fixed at its edges and having an intermediate resilient part arranged to be flexed downward by a plug threaded in the shell, a contact connected to said shell and arranged to be moved downward by the downward movement of said resilient part, a contact adapted to be connected to a line conductor and arranged to be engaged by said shell contact upon downward movement thereof, said shell and line contacts being normally separated.

4. In an electric socket, a screw shell, a resilient diaphragm closing the lower end of the shell This construction has obvious advantages and arranged to have a part thereof flexed downward by a plug threaded in the shell, said diaphragm being flxed at its edges, a contact connected to said shell and arranged to be moved downward by said diaphragm, and a contact adapted to be connected to a line conductor and arranged to be engaged by said shell contact when in its downward position, said shell contact being separated from said line contact when in its normal position.

5. In an electric socket, a base, a unitary assembly adapted to be inserted in the base comprising a screw shell having a sleeve at its lower end in which are carried a center contact comprising the other terminal of the socket, a line contact for'connection with a line conductor,

- when the socket is empty.

6-. Inan electric socket, a base, a unitary assembly adapted to be inserted in said base comprising a screw shell havinga sleeve integral with its lower end in which are carried a center contact comprising the other terminal of the socket; a contact adapted to be connected to a line conductor, and switching means adapted to complete a circuit between said line contact and one of the socket terminals when a plug is threaded in the socket, said switching means maintaining said circuit open when the shell is empty.

7. In an electric socket, a base, a unitary assembly adapted to be inserted in said base comprising a screw shell having a sleeve integral with its. lower end, a member of insulating material in said sleeve closing the lower end of the shell, a disk fixed in said sleeve and carrying a contact adapted to be connected to a line conductor, and

'means including a contact extending through said member for efl'ecting contact between said line contact and the center contact of a plug threaded in the socket, said contacts being separated when the socket is empty.

8. In an electric socket, a base, a unitary assembly adapted to be inserted in said base comprising a screw shell having a sleeve at its lower end in which are carried a center contact comprising the other terminal oi the socket, said center contact being engaged by a plug threaded in the shell, a member of insulating material closing the lower end of said shell, said: member having a flexible part adapted to be moved downward by a plug threaded in the shell, 8. contact below said member adapted to be connected to a line conductor, and means !or completing a circuit from said line contact to one of the socket terminals upon downward movement of said part, said circuit being normally open whereby said socket is insulated when empty.

9. In an electric socket, a base having a recess, socket terminals comprising a screw shell fixed to the side walls of the recess and a'center terminal carried therein, a member clamped between the base and the lower endof the screw shell carrying contacts adapted to be connected to line conductors, and a contact clamped between said member and the screw shell, said contact being normally separated from the line contacts and being movable downward into engagement with one oi the line contacts by a plug threaded in the shell.

10. In an electric socket, socket terminals comprising a screw shell and a center terminal, a

member at the lower end oi the screw shell carrying contacts adapted to be connected to line conductors, a disk of insulating material closing the lower end of the shell, said disk being fixed at its edges and having a part intermediate itsedges flexed downward by a plug threaded in the shell. and a resilient contact strip on the under side of the disk movable to a position completing a circuit between one of the socket terminals and one o! the line. contacts by downward movement of said intermediate part of the disk, said strip normally occupying a position in which said circuit is open.

11. In an electric socket, a screw shell, a disk of insulating material closing the lower end of the shell, said disk being fixed at its edges and having an intermediate part flexed downward by a plug threaded in the shell, a center terminal carried by said part, a resilient contact strip on the under side or said part connected to the screw shell and movable downward by downward movement of said part, and line contacts arranged to be engaged respectively by said center terminal and said contact strip upondownward movementoi' said intermediate part 01' said disk, said line contacts being separated from, the center terminal and contact strip when the socket is empty.

12. In an electric. socket, a screw shell, a disk of insulating material closing the lower end of the shell, said disk being fixed at its edges andhaving an intermediate part flexed downward by a plug by said disk into engagement with one of said line contacts, .said strip having 'an opening therein and being normally separated from said line con-- tact, and means for effecting connectionibetween the other of said line contacts and the center contact of a plug threaded in the shell through the opening in said strip.

' 13. In an electric socket, a base, a unitary assembly adapted to be inserted therein comprising a screw shell having a sleeve at its lower endand a center terminal comprising the other terminal of the socket, a member of insulating material carried in the lower end 01 the sleeve, line contacts carried by said member, a disk of insulating material closing the lower end of the shell clamped between said member and the shell, said disk having a part movable downward by a plug threaded in the shell, and means operable by downward movement of said part of the disk for completing a circuit between one of the line contacts and one of the socket terminals, said circuit being open when the socket is empty.

14. In an electric socket, a base, a unitary assembly adapted to be inserted therein comprising a screw shell having a sleeve at its lower end and a center terminal comprising the other terminal 01' the socket, a member of insulating material carried in the lower end of the sleeve, line contacts carried by said member, means spacing axially the socket terminal and line contacts,and switching means above said member for effecting a circuit between one 0! the line contacts and one 01' the socket terminals by threading a plug in the shell, saidcircuit being open when the socket is empty. I g 15. In an electric socket, a base, a unitary assembly adapted to be inserted therein comprising a screw shell having a sleeve integral with its lower end and a center terminal comprising the other terminal of the socket, a member of insulating material carried at the lower end of the sleeve, .line contacts carried by said member, a disk of insulating material above said member closing the lower end of the shell, and means between said disk and said member for efiecting a circuit between one of the line contacts and one of the socket terminals upon threading a plug in the shell. said circuit being open when the socket is empty.

'18. In sembly adapted to be inserted therein comprising a screw shell having a sleeve integral with its lower end and a center terminal comprising the other terminal of the socket, a member of insulating material carried at the lower end oi. the sleeve, line contacts carried on saidmember, a disk of insulating material clamped between said member and the shell, said disk having a part movable downward by a plug threaded in the shell, and means operable by downward movement of said part for effecting a circuit between one of the socket terminals and one of the line ,contacts, said circuit being open when the socket is empty.

17. In an electric socket, a shell adapted to receive a plug, a closed chamber including a flexible line conductors.

ROSCOE G. PHELPS.

an electric socket, a base, a unitary as 

